GLS periodograms of the three planetary systems’ raw (black, fitted RV offsets are subtracted) and residual (blue, full model subtracted) RV for one planet (all) and two planet (only Ross 128) models. Vertical lines mark the known (gray dashed) and inferred (solid blue) planetary periods P_planet, literature rotation period P_rot (solid red), half period (red dashed), alternative literature rotation periods P_rot,alt (red dotted; see Table 1), and GP periods, ρ (blue dashed). Horizontal lines mark the false-alarm probability levels shown in the figure legend. The colored arrow heads correspond to the vertical lines of the same color for parameters of this work (located at the top) or the literature (at the bottom). The period axis is scaled to match the extent of the recovery grids presented in Sect. 5.3.